This invention relates to a disposable diaper for absorption and containment of excretion. Japanese Patent Application Disclosure No. 1993-277149 describes a disposable diaper comprising a liquid-pervious topsheet, a liquid-impervious backsheet, a liquid-absorbent core disposed between these two sheets and a liquid-resistant upper sheet annularly, extending above the outer surface of the topsheet. The upper sheet is joined along its outer peripheral edge to the outer surface of the topsheet and formed substantially in its central zone with a longitudinally extending opening which is, in turn, provided along its peripheral edge with a longitudinally stretchable elastic member. With this known diaper, it is possible to prevent undesirable leakage of excretion disposed thereon from occurring along transversely opposite side edges and/or along longitudinally opposite ends of the diaper by the upper sheet which extends annularly above the outer surface of the topsheet and is joined along its peripheral edge to the topsheet.
However, the aforesaid Japanese Patent Application Disclosure No. 1993-277149 has a problem that, after urine and feces have been discharged into the opening, an amount of urine flowing on the topsheet may be mixed with loose passage, watery feces or even relatively solid feces since it is impossible for the diaper to separate feces from urine. Consequently even relatively solid feces may become watery and give the wearer an uncomfortable feeling if this watery mixture comes in contact with the wearer""s skin.
It is an object of this invention to provide a disposable diaper that reliably prevents undesirable leakage of urine as well as feces discharged on the diaper from occurring along both the transversely opposite side edges and the longitudinally opposite ends of the diaper, and reliably prevents urine and feces from being mixed together.
According to this invention, there is provided a disposable diaper having absorbent body, comprising a liquid-pervious topsheet, a liquid-impervious backsheet, a liquid-absorbent core disposed therebetween. A first liquid-resistant barrier wall annularly extends above a top surface of the topsheet. The absorbent body has transversely opposite side edge portions and longitudinally opposite end portions. The barrier wall is joined along a lower peripheral edge thereof to the body so as to define a first opening substantially in a central zone of the first barrier wall. An upper peripheral edge of the first barrier wall is elastically stretchable along the first opening. The barrier wall lies in a front half section of the absorbent body that extends from a vicinity of a center line bisecting a longitudinal dimension of the absorbent body toward a front end portion of the absorbent body or in a rear half section of the absorbent body that extends from a vicinity of the center line toward a rear end portion of the absorbent body. A liquid-resistant second barrier wall annularly extending around the first barrier wall lies in the front and rear half sections of the absorbent body. The second barrier wall has a lower peripheral edge portion joined to a peripheral edge of the absorbent body so as to define a second opening substantially in a central zone of the second barrier wall and an upper peripheral edge portion thereof has an elastic stretchably along the second opening.
The disposable diaper according to this invention functions as a barrier to prevent urine and feces discharged together from being mixed together even if one of such urine and feces tends to flow. Additionally, the barrier walls annularly extend on the top surface of the topsheet and thereby prevent leakage of urine and feces discharged onto the diaper from occurring along the transversely opposite side edges as well as along the longitudinally opposite ends of the diaper.